Overexpression of γ-glutamylcysteine synthetase gene from Caragana korshinskii decreases stomatal density and enhances drought tolerance

• Published in: BMC plant biology Vol. 21; no. 1; pp. 1 - 444
• Main Authors: Lu, Baiyan, Luo, Xinjuan, Gong, Chunmei, Bai, Juan
• Format: Journal Article
• Language: English
• Published: London BioMed Central 01.10.2021; BMC
• Subjects: Agricultural production; Auxin signaling; Auxins; Biosynthesis; Caragana korshinskii; Density; Drought; Drought resistance; Drought stress; g-Glutamylcysteine; Gamma-glutamylcysteine synthetase; Gene expression; Genes; Glutathione; Kinases; Leaves; Malondialdehyde; Moisture content; Photosynthesis; Physiology; Plant resistance; Plant stress; Polyethylene glycol; Proteins; Signaling; Stomata; Stomatal development; Transcription factors; Transgenic plants; Water content; Water loss; Water shortages
• ISSN: 1471-2229; 1471-2229
• DOI: 10.1186/s12870-021-03226-9

Abstract Background Gamma-glutamylcysteine synthetase (γ-ECS) is a rate-limiting enzyme in glutathione biosynthesis and plays a key role in plant stress responses. In this study, the endogenous expression of the Caragana korshinskii γ-ECS ( Ckγ-ECS ) gene was induced by PEG 6000-mediated drought stress in the leaves of C. korshinskii . and the Ckγ-ECS overexpressing transgenic Arabidopsis thaliana plants was constructed using the C. korshinskii . isolated γ-ECS . Results Compared with the wildtype, the Ckγ-ECS overexpressing plants enhanced the γ-ECS activity, reduced the stomatal density and aperture sizes; they also had higher relative water content, lower water loss, and lower malondialdehyde content. At the same time, the mRNA expression of stomatal development-related gene EPF1 was increased and FAMA and STOMAGEN were decreased. Besides, the expression of auxin-relative signaling genes AXR3 and ARF5 were upregulated. Conclusions These changes suggest that transgenic Arabidopsis improved drought tolerance, and Ckγ-ECS may act as a negative regulator in stomatal development by regulating the mRNA expression of EPF1 and STOMAGEN through auxin signaling.